Lithographic printing.



No. 686,574. Patented Nov. [2, IBM.

F. BILLING.- LITHHGRAPHIC PRINTING.

(Application filed July 22, 1901.\

(No Model.) 2 sheets-sheet l.

No. 686,574. I Patented Nov. I2, I90l.

F. BILLING.

LITHOGRAPHIC PRINTING.

(Apphcahon filed Jul 1901.)

2 Sheets-Sheet 2.

(No Model.)

WITNESSES UNITED STATES PATENT OFFICE.

FRANCIS BILLING, OF BIRMINGHAM, ENGLAND.

LITHOGRAPHIC PRINTING.

$PECIFIGATION forming part of Letters Patent No. 686,574,dated November12, 1901.

Application filed July 22, 1901.

To all whom it may concern.-

Be it known that I, FRANCIS BILLING, printer, a subject of the King ofGreat Britain, residing at Livery street, Birmingham, England, haveinvented certain new and useful Improvements in-Lithographic Printing,of which the following is aspecification.

This invention has reference to lithographic and other printingmachines, but principally to lithographic-printing machines in whichprepared zinc plates are used for printing from instead of the ordinarystones. Heretofore it has been the practice in securing such zinc platesin position upon the traveling bed of the machine to fasten them down atboth ends and also to bend one or both edges of the same over at a rightangle to the surface of the plate and then fasten each such bent-overpart between an edge of the said traveling bed and a detachable clamping-bar; but this method has several drawbacks in practice, theprincipal defect being that in consequence of the metal at the anglebetween the printing-surface and the bent edge striking against theinking-cylinders every time the bed is passed under them the metal atthis point rapidly wears away and cracks, and thus the plate soonbecomes useless. Further,in consequence of both ends of the preparedplate being fixed or secured to the traveling machine-bed by clampingdevices which grip the end edges when the forward end of the platepasses under the inking or other cylinders the pressure of the saidcylinders forces this part of the plate fiat down onto the surface ofthe bed, and as the other end is held and confined by its gripper, andtherefore unable to yield or give longitudinally in obedience to suchpressure, the middle parts of the plate are caused to buckle or cockleup, which is detrimental to'the results obtained in printing from suchplates, and, further, is apt to cause them to crack or breakthrough andso become useless.

According to my invention I propose to fix the plate to the bed at oneend only-viz. that end which passes first under the cylinders in theforward travel of the machine-while the other end is unrestrained andleft free to give or yield longitudinally, and thus the tendency tobuckle or cockle is neutralized or obviated. Further, by leaving an end.of

Serial No. 69,298. (No model.)

the plate loose, as described, it admits of the whole superficial areaof the said plate being kept fiat upon the bed when not actually passingthe cylindersby atmospheric pressure from above. I also propose tosecure the plate at the forward or fixed end without having to bend overthe edge at a right angle and by improved clamping means arranged insuch a manner that the said plate is prevented from being worn away orbroken in use, whereby the life of the same is very materially increasedand considerable economy is effected.

Figure l of the accompanying drawings represents a part of alithographic-printing machine, to the traveling bed of which a preparedzinc plate is secured at one end only in the manner and by the specialmeans constituting the present invention. In this view the top of thebed, the plate-clamping attachment, and the inking-cylinders are shownin section, while the base of the traveling bed and the rollers overwhich it runs are shown in elevation. Fig. 2represents, upon an enlargedscale and in longitudinal vertical section, the said bed and theattachment for securing the zinc plate thereto along oneend, the otherbeing left free or unrestrained to yield under the flattening pressureof the cylinders in the opposite direction to the forward travel of thebed and plate under the said cylinders- Fig. 3 is a plan of a part ofFig. 2, while Fig. 4 represents the component parts of the clampingattachment separated from one another and in section. Figs. 5 and 6 arerespectively transverse sectional views of the clamping-bars,illustrating slightlymodified means for swiveling the screw-bolts d tothe top clamping-bar d.

The same letters of reference indicate corresponding parts in theseveral figures of the drawings.

The improved clamping or gripping attachment by which the zinc plate ais secured to the forward end of the top side of the bed 12 consists ofa pair of metal'bars c and d, of suitable strength and of a length aboutequaling the width of the said traveling bed b. The bottom bar or base 0of'the attachment is secured either by bolts and nuts, such as 0' 0 orby'other suitable means to the front edge 17' of the bed -=-viz., thatedge which passes first under the inking-cylinders e in travelingforwardwhile the top clampingbar dis secured to the bottom one by aseries of screw-bolts d, the heads d of which preferably lie withinsinkings d in the bar, so as to present no upstanding or projectingparts liable to damage the inkingcylinders, although any otherconvenient connecting devices may be used to connect the two bars 0 and(1 together, with the forward edge a of ation of the inclined top edgeof the bar 0.

The body part of the other bar d of the attachment may be of any sectionthat will fit or lie within the space 0 comprehended by the angle of thebottom bar. The said top bar (1 has an overhan im extension or li dreferably running throughout its whole length and beveled at (1 upon itsunder side to correspond with the inclined edge 0 of the bottom bar, andit is between these two beveled surfaces that the edge of the plate isgripped and held in a plane slightly below that of the bed. The topsurface of the upper clamping-bar is also arranged in a plane slightlylower than that of the said bed, so as to insure it clearing theinking-cylinders when traveling to and fro with the bed, and its forwardedge is preferably inclined or chamfered at d to any desired extent, soas to be quite clear of the said rollers. By this arrangement the edgeof the plate is firmly gripped or held without being bent at aconsiderable angle or otherwise weakened.

The two bars may be secured or locked together with the plate betweenthem by any othermeansthanthosedescribed. Theclamping attachment issecured to the bed adjustably or otherwise by set-pins f, as usual, orby any other suitable means, or the edge of the bed may be furnishedwith a permanent fixture or be formed with a part corresponding in shapeto the bevel-edged bottom bar or base part previously described.

The application of my improvements to other printing-machin es in whichmetal plates are used in printing from difiers in no essential respectfrom its application to a zinc-plate litho-machine, as herein described.

The attachment-screws d of the clampingbar (1 may be swivelly connectedto the said bar, so that when they are rotated for withdrawal they liftthe bar with them sufficiently to liberate the plate and permit of itsremoval without having to completely detach the said bar, which makesthe said attachment easier to manipulate. This swiveling of the screwsmay be obtained by the employment of a confining-collar 01 asrepresented in Fig. 5, or by forminga circumferential groove d aroundthe neck of the screw, with which the point of a keeper-screw d passedthrough the bar engages, as represented in Fig. 6, thus confining thescrew to the bar, while still leaving it free to rotate.

Having fully described my invention, what I desire to claim and secureby Letters Patent is- 1. In a lithographic-printing machine, thecombination with the traveling bed for supporting the printing-plate andthe cylinders under which the bed is arranged to travel, of meansarranged contiguous to the forward edge of the bed and below the planeof the latter for affixing one end only of the plate to the bed, theother end of the bed being constructed to support the free andunattached end of the plate, substantially as described.

2. In lithographic printing from prepared zinc or other metal plates; aclamping attachment for securing ,to the traveling bed, only that end ofthe plate which passes first under the cylinders, the other end beingleft free or loose; consisting of a bottom bar such as c, fixed to thebed, and a top bar such as d, detachably connected to the bottom bar,with beveled or inclined gripping-surfaces c (1 between which the saidedge of the plate is gripped in a plane slightly below the top of thebed, as and for thepurposes set forth.

3. In a clamping attachment for securing the one end of a metallic plateto the traveling bed of a lithographic-printing machine; the combinationwith the fixed bottom bar 0 and the detachable top bar (1 having beveledgripping-surfaces 0 d of swiveling connection-screws d; confined to thebar dbut free to rotate therein, as and for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

' FRANCIS BILLING.

Witnesses:

ARTHUR T. SADLER, GAVIN RALSTON.

